1. Field of the Invention
The present invention relates to electrical motor protection apparatus, and more particularly to a resistive thermostat for electrical motor protection.
From the essential point of view, such protectors comprise a thermostat metallic device, with the corresponding pair of electrical contacts, and thermally coupled with the motor it intends to protect, and also an electrical resistor heater connected in series to the motor in order to heat the first, the assembly actuating so that, in case of any motor overheating, the combined heating effect of the thermal coupling with the motor and the electrical resistor heating system is such that results in the heating of the thermostat metallic device, being enough to configurationally deform it and separate the protector electrical contacts, thus interrupting the electric power feeding to the motor.
Concerning the real conceptive simplicity of such protectors, their currently existing constructive embodiments are extremely complex and expensive, including the unit external structure or body with multiple and varied cutouts, depressions, prominences and the like, such fact being also observed in the essential components themselves, also comprising a plurality of parts, further affected by several details of tabs, hotels, pins and the like, all such constructive complexity being naturally responsible for the major difficulties of its accomplishment and assembly, as well as increasing its cost, and further favoring the existence of disarrangements, lockings and other irregularities.
An object of the invention is to provide an improved protection for high currents and temperatures in electrical motors using a resistive thermostat apparatus.